The invention relates to a method for producing a security feature (1) in the form of a colored image (2), a colorant being applied to a substrate (3) to produce the image, the image (2) being subdivided into grid areas, immediately adjacent grid areas (4, 5, 6, 9, 10, 11) of the image (2) partially overlapping, an overlapping area (7, 8) of immediately adjacent grid areas (4, 5, 6, 9, 10, 11) being smaller than one of the grid areas (4, 5, 6, 9, 10, 11), grid areas (4, 5, 6, 9, 10, 11) of the image (2) being each assigned at least one color, and at least the areas of the substrate (3) corresponding to the respective grid areas (4, 5, 6, 9, 10, 11) minus the corresponding overlapping areas (7, 8) being covered with at least one colorant of the respectively assigned color, the overlapping areas (7, 8) between adjacent grid areas (4, 5, 6, 9, 10, 11) being covered at least with the colorant having the color assigned to one of the grid areas (4, 5, 6, 9, 10, 11) overlapping in the respective overlapping areas (7, 8).

The invention relates to a method for producing a security feature (1) in the form of a colored image (2), a colorant being applied to a substrate (3) to produce the image, the image (2) being subdivided into grid areas, immediately adjacent grid areas (4, 5, 6, 9, 10, 11) of the image (2) partially overlapping, an overlapping area (7, 8) of immediately adjacent grid areas (4, 5, 6, 9, 10, 11) being smaller than one of the grid areas (4, 5, 6, 9, 10, 11), grid areas (4, 5, 6, 9, 10, 11) of the image (2) being each assigned at least one color, and at least the areas of the substrate (3) corresponding to the respective grid areas (4, 5, 6, 9, 10, 11) minus the corresponding overlapping areas (7, 8) being covered with at least one colorant of the respectively assigned color, the overlapping areas (7, 8) between adjacent grid areas (4, 5, 6, 9, 10, 11) being covered at least with the colorant having the color assigned to one of the grid areas (4, 5, 6, 9, 10, 11) overlapping in the respective overlapping areas (7, 8).

Techniques for manufacturing a light field print using a printing press. The techniques include: identifying at least one characteristic of the printing press at least in part by printing at least one calibration pattern; obtaining content to be rendered using the light field print, the content comprising multiple scene views; generating, based at least in part on the content and the at least one characteristic of the printing press, a front target pattern and a back target pattern; and using the printing press to: print the front target pattern on a first side of a substrate; and print the back target pattern on a second side of the substrate.

Systems, devices, methods, and instructions for travel document validation, including receiving data for one or more travel documents, generating a set of features for artificial intelligence model training, validating, and testing, upon receiving data for a plurality of travel documents, data from a first subset of travel documents is used to train an artificial intelligence model, a second subset of travel documents is used to validate the artificial intelligence model, and a third subset of travel documents is used to test the artificial intelligence model.

In order to increase the security of value or security documents 100, a multi-luminescent security element 400 is provided which contains at least one first luminescence means 510 and at least one second luminescence means 520. The first luminescence means 510 can be excited under first excitation conditions Sp-1 for the purpose of luminescence, and the second luminescence means 520 can be excited under second excitation conditions Sp-2 for the purpose of luminescence, said second excitation conditions Sp-2 differing from the first excitation conditions Sp-1. The multi-luminescent security element 400 is additionally equipped with at least one absorber means 600 which prevents an excitation of the at least one first luminescence means 510 under the second excitation conditions Sp-2 for the purpose of luminescence.

In order to increase the security of value or security documents 100, a multi-luminescent security element 400 is provided which contains at least one first luminescence means 510 and at least one second luminescence means 520. The first luminescence means 510 can be excited under first excitation conditions Sp-1 for the purpose of luminescence, and the second luminescence means 520 can be excited under second excitation conditions Sp-2 for the purpose of luminescence, said second excitation conditions Sp-2 differing from the first excitation conditions Sp-1. The multi-luminescent security element 400 is additionally equipped with at least one absorber means 600 which prevents an excitation of the at least one first luminescence means 510 under the second excitation conditions Sp-2 for the purpose of luminescence.

A method and system for automatically verifying the authenticity of documents is provided. The method has: scanning a document to be verified in the visible and ultraviolet light spectrum; detecting in the scanned document digital watermarks printed with visible and ultraviolet ink; decrypting the marks, thereby obtaining an ultraviolet mark identifier and a variable data mark identifier; validating the percentage of the mark by checking for the presence of the digital watermark in different areas of the scanned document; comparing the mark identifiers obtained with mark identifiers stored in a database; and determining the validity of the document on the basis of the comparison. The invention allows the validity of the data printed in the document to be checked automatically, reducing the possibility of the undetected falsification, modification or total or partial alteration of a document.

A method and system for automatically verifying the authenticity of documents is provided. The method has: scanning a document to be verified in the visible and ultraviolet light spectrum; detecting in the scanned document digital watermarks printed with visible and ultraviolet ink; decrypting the marks, thereby obtaining an ultraviolet mark identifier and a variable data mark identifier; validating the percentage of the mark by checking for the presence of the digital watermark in different areas of the scanned document; comparing the mark identifiers obtained with mark identifiers stored in a database; and determining the validity of the document on the basis of the comparison. The invention allows the validity of the data printed in the document to be checked automatically, reducing the possibility of the undetected falsification, modification or total or partial alteration of a document.

The present invention provides photoluminescent iron-doped barium stannate materials absorbing ultraviolet (UV) light and exhibiting strong near-infrared (NIR) luminescence. Such materials exhibit increased integrated photoluminescence intensity in comparison to known BaSnO.sub.3 and iron-doped barium stannate materials, and therefore they are particularly useful for the production of photoluminescent security ink compositions and transparent covert security features with improved anti-counterfeiting resistance that can be used for protection of documents and articles against counterfeit and illegal reproduction.

The present invention provides photoluminescent iron-doped barium stannate materials absorbing ultraviolet (UV) light and exhibiting strong near-infrared (NIR) luminescence. Such materials exhibit increased integrated photoluminescence intensity in comparison to known BaSnO.sub.3 and iron-doped barium stannate materials, and therefore they are particularly useful for the production of photoluminescent security ink compositions and transparent covert security features with improved anti-counterfeiting resistance that can be used for protection of documents and articles against counterfeit and illegal reproduction.